A new TV drama is coming out about the life of the writer Ian Fleming. There's a lot of that sort of thing around at the moment. Because of our culture's lack of confidence in its ability to devise anything wholly new, a successful author's actual life becomes like a bonus work they wrote. No need to start readapting their stuff quite yet, because there's still the real life to do! And, brilliantly, it's marketable in the same way as all the recurring adaptations: as securely grounded in the old and good, rather than being new and now, contaminated by the unshakable rubbishness of contemporary us.

Illustration by David Foldvari.

"Real-life stories" also play brilliantly to the internet age's curious blend of credulity and scepticism. We'll queue up for dramatised biographies of creative giants because we believe they might have had genuine experiences comparable to their most captivating inventions – we believe that fiction can be secretly real but we're less willing to credit the creative spark, the writer's genius. We prefer to think that they just typed up a load of amazing stuff that happened to them and pretended it was pretend.

I find my own scepticism running in the opposite direction. Why should I think that anyone about whom the main famous fact is that they devoted a lot of their time to sitting alone, writing down things that popped into their head, had much of note going on besides that? Concentrating on writing is hard enough when there's an episode of Come Dine With Me just starting, let alone amid an actually interesting and dramatic biographical context. Writers write because they're bored or poor or both – and I'm afraid I don't want to see programmes about that. I prefer Downton Abbey.

But in the case of Sky Atlantic's Fleming, I don't need to worry because lots of it is made up. The show's star, Dominic Cooper, reassured viewers not to expect an accurate depiction of the writer's largely deskbound war years because the programme had taken "huge liberties" with the facts of Fleming's life. "There's what he says he did, there's what his biographers say he did, and then there's what we say he did," Cooper explained last week.

In consequence the show sounds quite diverting, with Fleming at various times machine-gunning and punching the Germans. "Everything is based on something real, but we have sexed it up at times," said the director, Mat Whitecross. "He didn't have any fisticuffs with Nazis, but it felt like it would be better if he did." I see what he means. Then again, as an alternative, Whitecross could have dramatised the life story of one of the tens of thousands of men who actually did hit Nazi soldiers – and then just stick in a scene at the end pretending that this bloke also wrote the James Bond books. Because, you know, it feels like it would be better if he had.

The show will carry the disclaimer that the events portrayed are "fictitious or have been changed for dramatic effect". But then the whole selling point of the programme – of any show that's about a real person – is that viewers will be watching a dramatisation of things that actually happened. And, in this case, that it might be a bit like a Bond film. Further investigation into Fleming's life revealed those two draws to be mutually exclusive. So the producers felt the best solution was to make a load of exciting stuff up, like Ian Fleming did, and then have Ian Fleming do them, like Ian Fleming didn't.

Is this cheating? I think so. Truth doesn't need to be as entertaining as fiction. The fact that something is a true story mitigates the flaws in its narrative: any dull bits, unsympathetic protagonists or unsatisfying plot developments. It also completely excuses, and indeed makes a virtue of, implausibility. If a true story is unbelievable, that's amazing and proves it was worth telling. If people say the same about fiction, it means it's badly written. So Fleming is pulling a fast one, despite the disclaimer. It's trying to put viewers into a non-fiction-appreciating state of mind so they'll find the stories more enjoyable than if they knew they were made up.

I thought people wouldn't stand for this. When the disclaimer came up at the end, they'd be incensed and shout: "Hang on, that's not fair! I thought I'd enjoyed that and now it turns out I didn't!" But that was before I heard about the British passion for sea angling. It's huge, according to Sea Angling 2012, a comprehensive Defra survey of the sport. This is odd, because fish stocks have plummeted and it's become nigh impossible to catch anything at all. But people go fishing anyway.

As Mark Lloyd, chief executive of the Angling Trust, said of his attempts to hook a sea bass: "It's slightly embarrassing for me to admit that the last one I caught was three years ago, off Dorset, but there is a great joy in angling that goes beyond catching fish." That was when I realised that people will stand for anything, sometimes up to their waists in freezing brine.

The Defra report says that more than a million people went sea angling in Britain last year and that, after adding up what they spent on equipment, boats and accommodation, the activity contributed £2.1bn to the economy and supported 23,600 jobs. Meanwhile, says the Angling Trust, only 12,450 are employed as commercial fishermen. So fishing as a hobby – for, on average, 1.6 fish per day apparently (or just over 0.3 fish per year if you're Mark Lloyd) – is of more commercial value than professional fishing for food. That's got to be the definition of a service-oriented economy.

So if the very fish that give fishing its raison d'etre have themselves been fictionalised, with no apparent impact on the popularity of the hobby, then the huge liberties taken with Fleming's life will seem tiny by comparison. After all, nothing is larger than a fish that doesn't exist. And, at the end of a contented day of imagining mackerel, we can all go home and watch Ian Fleming beat up the Nazis.